title: Reversible insulator-metal transition of LaAlO₃/SrTiO₃ interface for nonvolatile memory.
abstract: We report a new type of memory device based on insulating LaAlO₃/SrTiO₃ (LAO/STO) hetero-interface. The microstructures of the LAO/STO interface are characterized by Cs-corrected scanning transmission electron microscopy, which reveals the element intermixing at the interface. The inhomogeneous element distribution may result in carrier localization, which is responsible for the insulating state. The insulating state of such interface can be converted to metallic state by light illumination and the metallic state maintains after light off due to giant persistent photoconductivity (PPC) effect. The on/off ratio between the PPC and the initial dark conductance is as large as 10⁵. The metallic state also can be converted back to insulating state by applying gate voltage. Reversible and reproducible resistive switching makes LAO/STO interface promising as a nonvolatile memory. Our results deepen the understanding of PPC phenomenon in LAO/STO, and pave the way for the development of all-oxide electronics integrating information storage devices.
authors.affiliation: State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, P.R. China.
authors.forename: Hong-Liang
authors.initials: HL
authors.lastname: Lu
authors.forename: Zhi-Min
authors.initials: ZM
authors.lastname: Liao
authors.forename: Liang
authors.initials: L
authors.lastname: Zhang
authors.forename: Wen-Tao
authors.initials: WT
authors.lastname: Yuan
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Xiu-Mei
authors.initials: XM
authors.lastname: Ma
authors.forename: Da-Peng
authors.initials: DP
authors.lastname: Yu